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  • Flickering DMX when connecting newer Express /Expression consoles with older Reflection units

    The Relfexion / Reflection console has two modes for DMX pass-through: buffered and byte for byte.  (This is valid after software version 2.06). The latter mode sometimes fails on modern DMX consoles with the expanded speeds allowed by DMX512:1990.  Early version Reflexions were set to Byte-for-Byte, which can cause an inconsistent DMX data stream.  Buffered mode resolves these issues, and only introduces an imperceptible lag in the data stream.

    From the Reflection User's Manual (Version 2.xx)

    "In this mode [Buffered], incoming DMX data bytes are received under the highest priority interrupt and stored in a buffer in the battery-backed SRAM. The microprocessor also deals with interrupts (at the second priority level) from the output SIO whenever it has completed transmission of the latest output byte. At each output interrupt the microprocessor fetches the next byte in sequence from the input data buffer, passes it through the hardware calculator subsystem and finally sends the result to the output SIO. This therefore separates the timing of the incoming DMX and the outgoing DMX and allows the output DMX stream to continue smoothly even if the input DMX exhibits intermittent illegal timing or framing errors."

    To set buffered mode, open the unit and set jumper B on, i.e. shorted.  Jumpers are near the rear of the main PCB in between the transformer and ribbon cable connector.